An object of the present invention relates to a porous metal organic framework comprising at least one first organic compound and ions of at least one metal, with the skeleton of the framework being formed at least partly by the at least one first organic compound coordinating at least partly in a bidentate fashion to at least two ions of the at least one metal, where the at least one metal is lithium and the at least one first compound is derived from formic acid or acetic acid. Also provided a process for preparing the porous metal organic framework and its use for gas storage or separation.